Smokers with a past history of alcohol dependence (HP) have greater difficulty quitting smoking than smokers without such history (HN). This study compared the reinforcing effects of nicotine in HP and HN. 20 HP and 15 HN smokers matched on age, sex, and smoking habits were abstinent from smoking for 16 hours on each of 4 days. On days 1-3 of the study, Ss received 3 doses of 0, 2, or 4 mg nicotine polacrilex (total=0, 6, or 12 mg/day) in a randomized, double-blind, within Ss design. Ss completed the POMS after each dose. On day 4, Ss had lib access to all doses. During the reporting period 12/1/95-11/30/96, 43 Ss were enrolled in the study. Recruitment is now complete and one final batch of nicotine analysis is being run by the GCRC. Statistical analyses are under way and an abstract has been submitted for presentation at a national conference. Results now show HP Ss ingested more nicotine on day 4 (7.9 mg vs. 4.7 mg; p<.05), and were more likely to choose nicotine gum over placebo (85% vs 53%; p<.06). No differences in mood (POMS) were found. These findings indicate that nicotine is more reinforcing for HP Ss than NP Ss. Findings for mood effects are inconclusive. These data are consistent with findings that alcoholics have greater difficulty stopping smoking, and further suggest that smokers with past alcohol dependence are especially dependent on nicotine. Smokers with past alcohol dependence might especially benefit from nicotine replacement for smoking cessation.